Nukes on the 49th is a techno-thriller depicting a struggle of wills between American and Canadian political forces that eventually results in the Canadian Prime Minister deciding to develop nuclear weapons. Two American nuclear accidents on Canadian soil had pushed him over the edge.
Americans are appalled; they are paranoid about a nuclear power on their northern border, so close to major population and industrial centers. A majority of Canadians also disagree, but their reaction is tempered by their suspicion of American intentions towards Canada.
The President focuses American resources, including the CIA, elements of its military and its public relations might, against Canada. The CIA conspires with anti-nuclear supporters in Canada to destroy the nuclear weapons program.